Theory of Continuously Variable Transmission With Two Degrees of Freedom: Paradox of Mechanics

Recently creation continuously variable transmission (CVT) having property of the adaptation to variable technological loading develops. Traditional CVT contains the hydraulic converter and gear differential with two degrees of freedom (patents of Crockett, Volkov). The hydraulic converter imposes differential constraint on movement of links of the mechanism with two degrees of freedom. It provides definability of movement of transmission. Take place progressive CVT without use of the hydraulic converter (Harries’s patent, Ivanov’s patent). Such transmission contains only gear differential with two degrees of freedom. However the theoretical substantiation of serviceability of such transmission is not convincing for the lack of the proof of static definability of the mechanism with two degrees of freedom, having only one input. Ivanov K.S.’s theoretical researches do not contain enough convincing arguments of presence of definability of such mechanisms. Mechanisms with two degrees of freedom are considered disabled because of their contradiction to a key rule of mechanics that the number of the generalized coordinates should be equal to number of degrees of freedom of the mechanism (that is it should be equal to two, instead of to one). In Ivanov K.S.’s early works it was mentioned presence of paradox of the mechanics reflecting essence of the specified discrepancy. However in these works there was no the elementary demonstrative base of essence of the phenomenon resulting in static definability. The purpose of the present work to describe essence of the phenomenon which in certain conditions result to static definability of the mechanism with two degrees of freedom at presence only of one input, to receive the theoretical description of paradox of mechanics and its authorization using the elementary laws of theoretical mechanics. In the work the presence of paradox of mechanics is proved. The paradox of mechanics takes place in the kinematic chain having the closed contour, and it consist in the following. The structural group with two degrees of freedom having two consistently connected links is statically definable at presence only one entrance link. The paradox of mechanics is authorized by the account of additional constraint which is imposed by kinematic chain with the closed contour and two degrees of freedom on movement of links by a principle of possible works. Use of the equations of a statics and additional constraint allows to receive the equations of interrelation of parameters of transmission and to execute synthesis of transmission on the set conditions of motion. The found laws will allow creating the transfer mechanisms having property of mechanical adaptation to variable technological loading. Mechanical adaptation provides an opportunity of motion of an output link with a speed inversely force of resistance at constant input power.